I use 'sendmail' with PHP to send email. I can send to my gmail account (even though it goes to Trash). Email is return when I send to hotmail or other providers. Please see email '/var/log/maillog'.

Apple’s Mail.app can suddenly and inexplicably fail to send e-mail through SMTP (outgoing) servers. A few relatively simple fixes for this issue are as follows: Delete outbox folder In some cases, the ...